今天碰到一个非常奇怪的问题， 我使用Eclipse创建一个Vaadin的项目，然后使用jetty运行的时候，出现了下面的错误提示：
Suppressed: java.lang.RuntimeException: Error scanning entry com/vaadin/shared/ui/splitpanel/HorizontalSplitPanelState.class from jar file:///home/xiaoxiong/.m2/repository/com/vaadin/vaadin-shared/7.7.13/vaadin-shared-7.7.13.jar
at org.eclipse.jetty.annotations.AnnotationParser.parseJar(AnnotationParser.java:937)
... 6 more
Caused by: java.util.zip.ZipException: invalid LOC header (bad signature)
at java.util.zip.ZipFile.read(Native Method)
at java.util.zip.ZipFile.access$1400(ZipFile.java:60)
at java.util.zip.ZipFile$ZipFileInputStream.read(ZipFile.java:717)
at java.util.zip.ZipFile$ZipFileInflaterInputStream.fill(ZipFile.java:419)
at java.util.zip.InflaterInputStream.read(InflaterInputStream.java:158)
at java.io.FilterInputStream.read(FilterInputStream.java:133)
at java.io.FilterInputStream.read(FilterInputStream.java:133)
at org.objectweb.asm.ClassReader.a(Unknown Source)
at org.objectweb.asm.ClassReader.<init>(Unknown Source)
at org.eclipse.jetty.annotations.AnnotationParser.scanClass(AnnotationParser.java:1003)
at org.eclipse.jetty.annotations.AnnotationParser.parseJarEntry(AnnotationParser.java:984)
at org.eclipse.jetty.annotations.AnnotationParser.parseJar(AnnotationParser.java:933)
... 6 more
Caused by: java.lang.RuntimeException: Error scanning entry elemental/json/Json.class from jar file:///home/xiaoxiong/.m2/repository/com/vaadin/vaadin-shared/7.7.13/vaadin-shared-7.7.13.jar
at org.eclipse.jetty.annotations.AnnotationParser.parseJar(AnnotationParser.java:937)
... 6 more
Caused by: java.util.zip.ZipException: invalid LOC header (bad signature)
at java.util.zip.ZipFile.read(Native Method)
at java.util.zip.ZipFile.access$1400(ZipFile.java:60)
at java.util.zip.ZipFile$ZipFileInputStream.read(ZipFile.java:717)
at java.util.zip.ZipFile$ZipFileInflaterInputStream.fill(ZipFile.java:419)
at java.util.zip.InflaterInputStream.read(InflaterInputStream.java:158)
at java.io.FilterInputStream.read(FilterInputStream.java:133)
at java.io.FilterInputStream.read(FilterInputStream.java:133)
at org.objectweb.asm.ClassReader.a(Unknown Source)
at org.objectweb.asm.ClassReader.<init>(Unknown Source)
at org.eclipse.jetty.annotations.AnnotationParser.scanClass(AnnotationParser.java:1003)
at org.eclipse.jetty.annotations.AnnotationParser.parseJarEntry(AnnotationParser.java:984)
at org.eclipse.jetty.annotations.AnnotationParser.parseJar(AnnotationParser.java:933)
... 6 more
[INFO] Started ServerConnector@5ab4f1d9{HTTP/1.1,[http/1.1]}{0.0.0.0:9999}
[INFO] Started @8840ms
[INFO] Started Jetty Server
服务虽然起来了，但是界面上并不会出现想要的界面。 根据错误提示：
Caused by: java.util.zip.ZipException: invalid LOC header (bad signature)
于是我便去Google，发现了网上已经有人碰到过相同的问题：java.util.zip.ZipException: invalid LOC header (bad signature)
这篇文章最后给了个总结：
Replace the corresponding jar in the local Maven repository, then problem is solved.
在本地仓库中替换对应的jar文件，问题自然解决了。
让我很疑惑的是，我根据错误日志输出：
Caused by: java.lang.RuntimeException: Error scanning entry elemental/json/Json.class from jar
file:///home/xiaoxiong/.m2/repository/com/vaadin/vaadin-shared/7.7.13/vaadin-shared-7.7.13.jar
在本地仓库中对应的位置找到了提示中的jar文件，但是我少做了一步，没有使用反编译工具查看，错误信息中对应的class文件是否真的如提示的一般，没有存在。
而我最后的处理方式是： 直接把我本地仓库中对应的vaadin-shared-7.7.13.jar删除了，然后执行命令：mvn jetty:run -Djetty.port=9999, 发现它会自动将我们需要的jar包下载到本地，也没有了之前的错误提示。
那么为什么会出现java.util.io.ZipException呢？
通过Google我发现有这样一篇文章：why invked java.util.zip.ZipException?
里面有这样一句话：
This error was due to incomplete third-party downloads.
这个问题是因为出现了不完整的第三方jar包。